SUMMARY: The FAA is superseding an existing airworthiness directive (AD) for the airplanes listed above. That AD currently requires a one-time inspection of the main landing gear (MLG) shock strut assemblies for part and serial numbers; for certain MLG shock strut assemblies, a one-time inspection of the torque link apex joint, and corrective actions if necessary; and, for certain MLG shock strut assemblies, replacement or rework of the apex nut. This new AD continues to require the actions in the existing AD, and adds the previously omitted part and serial numbers.

This AD was prompted by reports of loose or detached main landing gear (MLG) torque link apex pin locking plate and the locking plate retainer bolt in the torque link apex joint. The FAA is issuing this AD to detect and correct improper assembly and damage of the MLG torque link apex joint, which could cause heavy vibration during landing, consequent damage to MLG components, and subsequent collapse of the MLG.